Express the sum of 7.68m and 5.0m using the correct number of significant digits.
12.7 m
A substance that forms a vapor is generally in what physical state at room temperature?
Liquid and Solid
Which of the following is true about homogeneous mixtures?
They are known as solutions
All of the following are physical properties of a substance in the liquid state EXCEPT
indefinite volume
What information is needed to calculate the percent composition of a compound?
The formula of the compound and the atomic mass of its elements
An example of an extensive property of matter is
Mass
Which of the following was NOT among Democritus' ideas?
Atoms retrain their identity in a chemical reaction.
In a heating/cooling diagram, specifically a heating diagram. What do A, C, and E represent?
Thermal energy, increasing as time progresses
In a heating/cooling diagram, specifically a heating diagram. What do B and D represent?
Phase energy, also increasing as time progresses
During region D in a heating diagram, the energy being absorbed is...
Increasing the distance between the particles and increasing their phase energy.
If the solubility of a particular solute is 10g/100gH20 at 20 Celsius, which of the following solution concentrations would represent a super saturated aqueous solution of that solute
11g/100gH20 at 20 Celsius, as you're increasing the solute for the solvent that it would dissolve in.
The molar mass of a certain gas is 49 g. What is the density of the gas in g/L at STP?
2.2 g/L [49g (mass)/22.4L at STP (volume)]
What is the empirical formula of a substance that is 53.5% C, 15.5% H, and 31.1% N by weight?
C2H8N1